unload in firefox

I have a client register startup script like so:

" " + "document.body.onunload = clea开发者_如何学JAVArSession; " + "";

The script works fine in IE8 by calling the clearSession() client script but not with firefox. can anyone help please?

thanks

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Use window.onunload instead?

https://developer.mozilla.org/en/DOM/window.onunload